Required practical 8 - Distil a product from a reaction

What is needed for the partial oxidation of primary alcohol to aldehyde or secondary alcohol to ketone

Pottasium dichromate solution and dilute sulfuric acid. Warm gently and distil the aldehyde as it forms.

What is the colour change that can be seen?

Orange to green.

What is the saftey concern with pottasium discromate?

Wear gloves as it is toxic and a carcinogen.

Describe the method of the partial oxidation of a primary alcohol.

Use limited quantitiy of oxidising agent and distill product immediatley as it is formed.

Place 10cc dilute sulfuric acid and add 3g of pottasium dichromate and antibumping granules

Add 1.5 cc of primary alcohol in drops from a dropping pippette. Shake the flask.

Heat and slowly distil 2cc of liquid into a test tube, making sure none of the reaction mixture spills over.

Which way does the condenser work?

cold water moves in from the bottom so it goes against gravity and allows more efficent cooling and prevents backflow of water.

What is the difference in the method when making carboxylic acid from primary alcohol?

don't use dilute sulfuric acid, heat under reflux and distill off product AFTER reaction has finished.

What is the purpose of antibumping granules?

prevent vigorous, uneven boiling by making small bubbles for instead of large bubbles.

Why would you not seal the end of a condenser?

build up of gas pressure could cause the apparatus to explode, this is true of any apparatus where volatile liquids are heated including the distillation set up.

What do you do when you ave liquids with different boiling points?

Fractional distillation.